A vehicle differential is supported on the vehicle's rear sub-frame which, in turn, is mounted to the body of the vehicle. Specifically, shafts on the differential fit into mounts supported on the sub-frame. When the vehicle is involved in an accident such that the differential is displaced (typically a frontal impact), it is desirable that the differential is separated from the mounts to avoid impact force being transmitted through the differential to vital vehicle components where significant damage can be caused. It is desirable to have the differential rotate downward after separation from the mounts and away from other vehicle components that could otherwise be damaged.
In the art, as shown if FIG. 1, metal mounts are known that include an outer metal housing member and an inner ring member separated by a rubber bushing. When a certain amount of force is applied to the metal mount via movement of a differential support shaft held in the inner ring member, in an axial direction, the inner ring member is forced out of the outer housing member through failure of the bushing and the differential is effectively separated from the vehicle sub-frame so significant damage to other vehicle components is avoided. However, the differential shafts must be moved a distance equivalent to the width of the outer housing in order to have sufficient clearance from the mounts to separate.
In more compact vehicles, it is desirable for the differential to separate from its mount(s) at much lower force thresholds, i.e. shorter displacements of the differential support shafts. The known metal mounts cannot be adjusted to provide separation of the inner ring and outer housing at such a lower force threshold.